it all depends on if, and how much you are willing to pay.
I have tried a couple of routes for my upcoming release.
One, which is beginning to annoy me now, was that one of my friends is a fantastic manga/anime artist but is completely unreliable!!
The second was to search google images and although the pictures are mostly copyrighted, I have then found details of the artists and contacted them. One wanted €200 to release the rights of his drawing to me. However, the second artist I contacted was more than happy to let me use his drawing free of charge, provided that I creditted him and put a link/details of his gallery website in my book.
The KDP Cover creator works pretty good. You can even use your own images (That you have rights to) or buy them from shutterstock.com Very easy to use. Bt if you want something very stylistic you will need to employ a graphic artist
I would recommend Mae at Coverfreshdesigns.com She designed the covers for all my books at a very reasonable price. She is quick - usually has a draft proof for you to consider within 3 days.
Depending on what you are doing, I would recommend fiverr.com
There are some very good and experienced ebook cover experts available for a very reasonable price.
It's a good idea to check their ratings, however, to make sure you get someone who knows what they are doing.